贯叶金丝桃的电子束辐照杀菌研究

研究电子束辐照贯叶金丝桃杀菌的可行性,为科研和生产中有效地应用该方法提供理论依据。辐照样品中微生物数量的测定依据《中华人民共和国药典》提供的方法;应用高效液相色谱检测有效成分金丝桃素和金丝桃苷含量;依据微生物存活对数与辐照剂量的线性关系,求得D10;采用目测、鼻嗅、品尝的评定方法,评定样品辐照前后的外部性状变化。结果表明:细菌、霉菌+酵母菌的D10值分别为2.91 kGy和4.69 kGy,霉菌和酵母菌相对于细菌对电子束有更强的耐受力,适宜的辐照加工剂量为4.5~6.5 kGy,经过辐照后,样品可以保存30~150 d,卫生指标仍达到国家药典中规定的中药粉剂微生物限度标准,金丝桃苷和金丝桃素的含量未发生显著变化。因此,利用电子束辐照贯叶金丝桃杀菌是一种行之有效的方法。     

野生及栽培贯叶连翘提取物中金丝桃素含量比较研究

针对目前国际上日渐重视金丝桃素的应用情况，建立了简单的高效液相色谱(HPLC)测定野生及栽培的贯叶连翘提取物中金丝桃素的含量，回收率分别为98．6％和97．2％，相对标准偏差分别为1．2％和1．6％(n=4)。该法灵敏度高，最小检出量低，有良好的重现性和精密度。     

金丝桃素提取、分离方法的研究

目的:研究贯叶连翘中有效成分金丝桃素提取方法。方法:应用有机溶剂溶解法、薄层色谱法、紫外检测、高效液相色谱(HPLC)等方法探讨贯叶连翘中金丝桃素提取方法。结果:用石油醚除叶绿素、花青素,以丙酮为溶剂在60℃水浴中提取贯叶连翘中金丝桃素和酮类衍生物,在真空度为0.07MPa、温度为60℃水浴条件下浓缩。后用100-200目硅胶分离金丝桃素,钢瓶冻干,得含金丝桃素为1.08%深红色产品。     

金丝桃素蛋白络合物体外抗H5N1亚型禽流感病毒的活性研究

用鸡胚法进行了金照桃素蛋白络合物抗HSNI亚型禽流感病毒活性研究。分别采用了感染病素同时给药、给药后接种病毒、先感染病毒后给药三种方式，通过测定鸡胚尿囊液的血凝效价和计算药物对感染鸡胚的保护率，观察金丝桃素蛋白络合物的抗H5N1亚型禽流感病毒活性。实验结果表明，①药物在体外与病毒作用一段时间后不规则将其混悬液接种鸡胚，药物浓度在0.5mg/ml以上时，对感染鸡胚的保护率达100%。同时给药组的血凝效价显著降低，与对照组相比差异极显著；②在感染病毒前给药，药物浓度在2mg/ml以上时，对感染鸡胚的保护率达100%，药物组的血凝效价显著降低，与对照组相比差异极显著；③先感染病毒后给药，药物浓度在2mg/ml以上时，对感染鸡胚的保护率达88.9%，血凝效价明显隆低，与对照组相比差异显著。同时，在此种方式下，药物对病毒的抑制作用与药物浓度有一定依赖性，适当提高药物浓度，可以增强其抗病毒活性。     

金丝桃素对口蹄疫病毒的体外抗病毒实验

本文报道了金丝桃素体外抗口蹄疫病毒（FMDV）的研究结果。采用双抗体捕获抗原法、病毒滴度测定、MTT法、组织细胞培养等方法均检测到抗病毒作用。结果显示：金丝桃素在BHK-21细胞感染FMDV前、后及同时加入，都有明显抑制细胞病变的作用。金丝桃素使FMDV的TCID50从8．5下降到6．25。双抗体捕获抗原法检测到金丝桃素有效抑制FMDVBHK-21细胞的吸附、融合，抑制率可达59．72％。研究结果提示：金丝桃素在体外有抗口蹄疫病毒作用，抑制口蹄疫病毒与宿主细胞的吸附、融合是抗病毒的重要途径之一。     

Sunlight associated hyperthermia as a consistent and rapidly developing clinical sign in sheep intoxicated by St John's wort (Hypericum perforatum)

OBJECTIVE: To assess the usefulness of rectal temperature responses in Australian bred Merino sheep, following the oral administration of Hypericum perforatum (St John's wort), as an early indicator of Hypericum intolerance. DESIGN: Thirty-three Merino ewes were divided into three groups of 11. Each group was dosed with finely ground, dried, flowering growth stage H perforatum plant material at either 5.7, 4.0, or 2.85 g dry plant per kg live weight. This corresponded to 5.3, 3.7 and 2.65 mg hypericin per kg live weight, respectively. PROCEDURE: The sheep were dosed with a plant slurry by stomach tube and then exposed to bright sunlight for up to 5 h per day over successive days. Their clinical responses were observed and rectal temperature measured. RESULTS: Ingestion of H perforatum followed by exposure to bright sunlight frequently resulted in clinical signs attributable to skin irritation and central nervous effects, including an inappropriate increase in body temperature. A decrease in H perforatum ingestion from 5.7 to 2.85 g dry plant per kg live weight and a corresponding decrease in hypericin ingestion from 5.3 to 2.65 mg per kg live weight, was associated with a decrease in the severity of the clinical signs, including the severity of the hyperthermia. CONCLUSIONS: The rectal temperature rise in affected sheep is a reliable indicator of the early development of an adverse clinical effect. There appears to be an absolute requirement for exposure to bright sunlight before any effects of H perforatum will develop. A single dose of H perforatum remains potentially effective for up to 4 days. In the small group of Merino sheep tested a tolerance level for H perforatum, eaten at the flowering stage, of < 1% (plant wet weight) of body weight and a tolerance level for hypericin of < 2.65 mg per kg live weight, were demonstrated.     

Agronomic and chemical characterization of 39 Hypericum perforatum accessions between 1998 and 2000

Thirty‐nine accessions of St John's Wort were studied over a 3‐year period. The percentage of diseased plants ranged from 0 to 100%. After 3 years of cultivation, 18% of the accessions presented a dieback rate of <10%. Hypericins and hyperforins in flowering tops (top 30 cm of plants at full bloom) and flowers were assayed using high‐performance liquid chromatography (HPLC‐DAD Diode Array Detector) (one to three cuttings a year). The hypericin contents in flowering tops ranged from 0.7 to 3%. These levels were, on average, 2.8‐fold lower than those recorded in flowers. Hyperforin levels varied in the different accessions, ranging from 0.65 to 3% in flowering tops and 2 to 5.7% in the flowers. In line with present industrial needs, a minimum content of one or more of the active components, it will therefore be necessary to select accessions in terms of the dry weight yield and the contents of flowering tops and flowers. Dry weight depends on cutting height, which also affects the quality of the plant material harvested. Because of the plant to plant variability, the performance of the accessions selected would be improved.     

应用响应面法优化金丝桃素的纯化工艺

在单因素试验的基础上,根据中心组合试验设计原理,选择上柱液中金丝桃素的浓度、洗脱液中乙醇的浓度和洗脱液用量为考察因素,以产物中金丝桃素含量为响应值,采用3因素5水平的响应面分析法对NKA-9型大孔树脂分离纯化贯叶连翘中金丝桃素的工艺条件及参数进行优化.结果表明:金丝桃素的最佳纯化工艺条件为上柱液中金丝桃素的浓度37.6...     

贯叶连翘引种驯化过程中生理生化特性、活性物质含量及抗氧化能力的变化

为了探明贯叶连翘引种驯化过程中生长适应能力以及活性物质的变化,以野生和栽培盛花期植株为材料,分别对生理生化特性、活性物质含量以及抗氧化能力进行了测定与分析,结果表明,栽培贯叶连翘的净光合速率、蒸腾速率、气孔导度、叶绿素含量和根系活力均高于野生植株,尤其是其盛花期和地上部分干重分别较野生植株提前了7 d和提高了16.67%。总黄酮和金丝桃素含量在栽培和野生植株同一器官中无显著差异;总酚类在野生花中的含量显著高于栽培花,而叶中的含量则相反;野生和栽培植株各器官中,总黄酮和酚类化合物含量在叶和花中的含量显著大于茎,而金丝桃素的含量表现为花>叶>茎。野生和栽培各器官抗氧化能力为叶>花>茎,其中,野生和栽培叶、茎提取液的抗氧化能力无显著差异,而栽培花的抗氧化能力显著大于野生花。以上研究结果表明,贯叶连翘野生转栽培后,不仅具有较好的生长适应能力,而且主要活性物质的积累量及抗氧化能力并未显著降低。该研究结果将对贯叶连翘种植栽培以及保护野生资源具有重要的参考价值和实践意义。     

RP-HPLC测定贯叶连翘中的金丝桃素含量

采用反相高效液相色谱法测定了贯叶连翘提取物金丝桃素浸膏中金丝桃素的含量。用Kromasil C18(5μm,250×4.6 mm)色谱柱为固定相,乙腈-水(140∶10)为流动相,流速为1 mL/min,检测波长为284 nm。结果金丝桃素的含量为0.914%,平均回收率为96.76%,日内精密度RSD为2.67%,日间精密度RSD为3.65%。